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telomerewhythere writes "Michael Strano and his team at MIT have made a self-assembling and indefinitely repairable photovoltaic cell based on the principle found in chloroplasts inside plant cells. 'The system Strano's team produced is made up of seven different compounds, including the carbon nanotubes, the phospholipids, and the proteins that make up the reaction centers, which under the right conditions spontaneously assemble themselves into a light-harvesting structure that produces an electric current. Strano says he believes this sets a record for the complexity of a self-assembling system. When a surfactant is added to the mix, the seven components all come apart and form a soupy solution. Then, when the researchers removed the surfactant, the compounds spontaneously assembled once again into a perfectly formed, rejuvenated photocell.'"

Now all we need is to mimic Chlorophyll F and start capturing everything from beginning IR (720nm) on down. I'd love to see a solar cell that can respond to all of the wavelengths currently covered by terrestrial and marine plant life.

The technology's best application is probably in outer space, where we don't have to worry about wavelengths (since there's so much more sun out there). I can even envision its application as a possibly more compact plant substitute for the life support system of a long-duration space flight, say, to Mars.

I hate to be a crazy fanboi, but is this a "Holy shit" news moment?? I have been telling my middle school geography students for years that plants can harness solar power cheaply and easily. Are plants smarter than us? Maybe we are turning a corner with this one. Watch out plants, we are on to you! And we just might be on to the greatest break in energy production known to mankind. Once we harness the power of the sun we step up a rung on the advanced civilization ladder. Hooray for bad ass MIT scientists!!

Are they smarter then us. No but many are more evolved then us. Plants have been around evolving on land much longer then the first bug left the oceans. They are quite adapted to their environment. Now humans and mammals are not so evolved but our evolutionary path took a different way where a more organized central nervice system took presendance over energy gathering.

No but many are more evolved then us. Plants have been around evolving on land much longer then the first bug left the oceans. They are quite adapted to their environment. Now humans and mammals are not so evolved but our evolutionary path took a different way where a more organized central nervice system took presendance over energy gathering.

That's not quite the best description of evolution. It isn't a race to some endpoint, there really isn't much that can be classified as 'less evolved or more evolved' unless you slice the requirements so thin that only one organism could survive based on such criteria and therefore make the whole concept of evolution meaningless. Let's say a landslide washes a very niche species of plant into the ocean where the saline content promptly kills the entire species. Does that make a salmon more evolved since it didn't die?

And for that matter, unless we assume some multiple genesis theory for life on Earth, every species today has been subject to evolutionary forces for the exact length of time as any other species.

I thought you could pick a common starting point for related species or maybe a period of time for unrelated species and ask how different is this species today compaired to what it was then (at least hypothetically if it's impossible to do so pratically). The one with the greatest genetic drift would be considered to have evolved more.

Whether that's good or bad for it is left up to contention. If a creature is perfectly built for a location, then it will eventually become the least evolved creature.

But still the best!

It is a shame that you posted as an AC, because that is a fairly insightful post.

People seem to confuse evolution with something that rewards the 'peaks' with survival, yet what it actually does is reward the most efficient with respect to that system. Any trends with regard to evolution, are those that progress toward effi

The one with the greatest genetic drift would be considered to have evolved more.

One of the issues with this is that we do not know the 'in between'. It is possible that a species may have evolved to a middle phase, but then evolved back to something which appears to be similar to the original.

Of course such a claim requires evidence, and you can find instances of this in species today. Consider chickens. There is a gene, which if activated, will cause the chicken to grow teeth, much like we expect their distant ancestors to have had. But even further back, their ancestor's ancestors may not have had teeth at all.

Of course, the distant ancestor's ancestors genetic code likely did not have the code for teeth in the first place, and you could look at that as evidence for your 'more evolved' Yet it is possible that some genes were evolved and discarded in a manner so that there is no trace that they were there in the first place. Color vision in mammals is another trait that is suspected to have been evolved, discarded, and lately reintroduced.

Yet ignoring all that, if we WERE to base the concept of 'more evolved' on genetic drift from the source, then the concept that plants are 'more evolved' seems to be false given that plants tend to be much more genetically 'stable' than animals. We find very similar relatives to today's plants in the fossilized remains, yet if we were to compare todays animals with those found before the dinosaurs, one could only conclude that 'more' evolution (in the form of genetic drift) occured in animals than plants.

That said, I still stand by my original statement that when it comes to evolution, it is nearly pointless to try and classify levels or extent of evolution as if it were some sort of race.

Genetic analysis is not my area (I prefer structure to sequence) but I understood from a book called "Deep Time" on cladistics that it is really only informative to compare THREE species at a time, not two.

So, saying "chimps are similar to humans" is less meaningful than "chimps are more similar to humans than lemurs". All life forms on earth share some points of similarity.

Hmmm. Maybe that wasn't relevant to the question of : "Is X more evolved than Y?" but I guess I was thinking of the last common ancesto

Doesn't something having gone through more evolution mean that it the process didn't "get it right" the first time? As I recall certain groups of animals - sharks, turtles, alligators - are essentially unchanged for millions of years.

That does sort of boggle the mind, though, how something could essentially just remain the same. The most common examples are often carnivorous predators, too.

Whether the evolution of the global ecosystem and each of its parts is in some grand sense moving forward or just changing a lot is not a scientifically decidable question, at least for the foreseeable future. The structure of the question depends on faith: either faith in Gaea or some other Supreme Being, or an equally strong faith that no such being exists. As a neopagan of the witchy type, I personally believe that the most evolved way to handle these kinds of issues is to learn to dance smoothly and qui

The structure of the question depends on faith: either faith in Gaea or some other Supreme Being, or an equally strong faith that no such being exists.

It's not a matter of faith, it's a matter of evidence. Applying Occcam's Razor says that the process of evolution doesn't need such a being, and there is no evidence for Gaea. There is always room for further evidence, however.

As a neopagan of the witchy type, I personally believe that the most evolved way to handle these kinds of issues is to learn to dance smoothly and quickly between the two different world views. But i recognize that the idea of deliberately Crafting one's life is not acceptable to a lot of people. For one thing, it takes a great deal of time and effort that will go unrewarded by anyone else: others don't even see what you are doing.

This is where evidence comes into play. Do you even see what you are doing? Are you just deluding yourself?

That would make it too easy to lose sight of Salmon's partnership with Bear and Eagle to fertilize the otherwise barren heights of the Pacific Northwest with then nutrients from the ocean that make the region's forests so richly verdant.

And do you want to talk about whatever partnerships produce deserts or ice ages?

It's not a matter of faith, it's a matter of evidence. Applying Occcam's Razor says that the process of evolution doesn't need such a being, and there is no evidence for Gaea. There is always room for further evidence, however.

I find your faith in Occam's Razor... amusing.

Within the limitations of the world view you espouse, your argument is irrefutable. It is just that you are proselytizing in a very public forum for a rather limited world view, and thus possibly affecting an unknown number of others who have yet to think these issues through. I regard that as unfair to those in the audience who have the mental capabilities to learn to dance between world views without shackling themselves to any particular one. So I argue wit

I don't see how it is any more unfair than your proselytizing, though I'm not advocating a religion. You're the one talking about witchcraft and animism or totemism or whatever the hell it is you believe in.

Your insistence that the only true model of the world is the scientific model could cause some these persons to turn their backs on an enriching source of knowledge, and that would be like poisoning another person's well. Don't do that.

Your insistence that people should believe in fantasies is dangerous. I won't insist you stop doing that, as I believe in freedom of speech. I would only ask others to think critically and skeptically, and know that lots of bullshit has been sluiced away by doing so.

I don't see how it is any more unfair than your proselytizing, though I'm not advocating a religion.

It was your proselytizing for the dogma of science as you see it that provoked my response. I do not volunteer my beliefs, let alone assert them as something others should adopt; I do not proselytize. As you point out with some evident frustration later in your post, I do not even say what my beliefs are. I sometimes respond to your type of proselytizing when it occurs in certain public forums, as I have done here. I rather believe that Galileo would respond in the same fashion were he to see your posts, si

Wow - that manages to both misunderstand quantum mechanics and mysticism. There's nothing mystical about quantum mechanics - it defines what we can and cannot measure in an incredibly precise, rigorous and above all completely testable mathematical fashion.

It was your proselytizing for the dogma of science as you see it that provoked my response. I do not volunteer my beliefs, let alone assert them as something others should adopt; I do not proselytize.

The nice thing about debating on Slashdot is that the posts are archived and uneditable. You are the one who provoked my response. You did indeed volunteer your beliefs. "As a neopagan of the witchy type", "Crafting one's life", "to even talk about that role of Salmon requires dancing away from the scientific mind set and into the totemic mind set".

As you point out with some evident frustration later in your post, I do not even say what my beliefs are.

Well you did, as I showed. My "evident frustration" was an expression of scorn for the exact details about the mumbo-jumbo you were espousing.

I rather believe that Galileo would respond in the same fashion were he to see your posts, since his biographies suggest that he really hated it when anyone tried to insinuate their dogma into a discussion in such a way that others would accept it without critically assessing it.

slightly less trolling than to the faith in Occam's razor guy.your a comfortable secular humanism.

would that be on with or without Maya? personally I think some Buddhists have Maya for thinking animals/people are special. oddly my partner seems to have partial Maya, she's aware of it, but only partially.

QM rigorously defines a pinhole through which those who have confined their thinking to the box of the empirical method must recognize that there is Mystery: that which cannot under any circumstances be known. Quantum foam shows that when you extend the QM model beyond simple particle interactions you find that this Mystery is involved at the margins of every little thing, and thus implicated in every interaction between different things: there is a little bit of unknowable in everything that happens. If yo

You confuse my beliefs, which I have not expressed, with some very broad descriptions of general belief systems that I mentioned solely as background. You then defend yourself against my correction of this by admitting that you are responding emotionally, with "an expression of scorn", rather than rationally.

I could go on, but that is sufficient reason to conclude that there is no further rational discussion possible. Have a good day.

It's just as well you're finding a flimsy excuse to run away, as I can't have a rational discussion with a liar. I mean, you explicitly said "As a neopagan of the witchy type" and talked about the benefits of "Crafting". You then proceed to ignore all the rational arguments that follow and pick on one expression of scorn, after you yourself threw out such phrases like "They simply have less evolved minds.". Do these "evolved minds" lead people to become liars and ignorers of evidence?

Showing a method of deriving pi does not render it any less irrational. Any real world application that involves pi carries an intrinsic amount of the unknown that has nothing to do with imprecision in measurement.

Just accept that none of our models can perfectly match reality, and recognize that our physics is all about our models, and about nothing other than those models. The real universe is unknowable. Get used to it.

I think current thinking is that the universe is a bit like a big string (which may itself be interacting with something that it not itself, a greater universe).

That is a 4d torus.So that could be seen as somewhat ballenced.

And for something like time it could always go forwards (so be asymmetrical in that way), but a lack of latent momentum through time could be, for instance, clock-wards or anti-clock-wards collapsed 'motion' [size etc..] through space.

The central premise is that the best that our minds can do is make some pretty durn interesting models of reality, and play around with those. And sometimes the models lead to some interesting technologies that help put food on the table, keep a roof overhead, or keep the wolves away from the door.

But it is a serious mistake to confuse these models with reality. When talking about the laws of physics, as soon as you step away from the models and

A circle can be expressed as something at which the probability of an something else radiating from a central origin.... whatever dependant upon if you class a circle in-situ.

That may or may not screw your mind. I could elaborate on whatever, and limits are probably! required, certainly induction.The central origin, doesn't mean that the radiant thing is singular, nor circular. The model is also dependant upon how you desire interference to be taken into account.I al

About the second law of thermodynamics being the same as Occam's razor: no, I don't think so. At least not in the known universe.

Of course the existence of this conversation demonstrates that the laws of thermodynamics are only applicable within the limits of physics model that frames them, and do not apply to reality itself. For if it were otherwise, there would be no life nor any other self-organizing systems. Think of this as one of the trivial applications of the anthropomorphic principle.

Parent post (along with many others) is confusing Occam's razor with parsimony. These are only superficially similar. Quirks in the English language can make it hard to appreciate the difference, but it is very definitely there.

Parsimony: as expressed above.

Occam's razor: when presented with two hypothetical processes that suggest identical outcomes, choose the simpler one (since it will be easier to test). Note that there is nothing here to indicate that reality might be one way or the other. Occa

It is also worth pointing out that the second law of thermodynamics is better expressed as "a closed system tends toward maximum entropy".

Unfortunately it is very difficult to construct a closed system in anything but your imagination. A few decades ago, the common belief among physicists and cosmologists was that the Universe was a closed system. Now no one is so sure about that. From another side, the implications of the discovery of chaotic processes and of fractals suggest that it might be impossible

to be fair, I did miss quote it (ref my other post to GP). But transcendentally it doesn't make any difference.also, game theory. I didn't put Nash equilibrium, I put that point, I'm not sure how a complex system has a point, unless you count a moment.

Solar power does work great for plants, but I wouldn't say they are better at energy production then us. Plants are only able to convert about 5% of the light that hits them into energy. That low efficiency is adequate for them only because their energy requirements are so low. They barely move, and they don't have complex, power hungry brains.

Plants are only able to convert about 5% of the light that hits them into energy. That low efficiency is adequate for them only because their energy requirements are so low. They barely move, and they don't have complex, power hungry brains.

You realize, of course, that your last sentence also describes the average American in their living room. Therefore, this plant based approach might be a good one to emulate in our goal to reduce petrochemical use.

Now all we need is to mimic Chlorophyll F and start capturing everything from beginning IR (720nm) on down. I'd love to see a solar cell that can respond to all of the wavelengths currently covered by terrestrial and marine plant life.

You're in luck.

Existing solar cells do capture everything from 720 nm on down-- in fact, silicon responds out to about 1000 nm. Existing solar cells do respond to all the wavelengths currently covered by terrestrial and marine plant life.

Actually, no. If you look at the color of the solar panel, you'll find its wavelength gap that it doesn't pick up light from, as that's what is being essentially reflected back to you.

Most solar panels work best under green and red light, and deeper violets, IR has typically had too low of an energy potential to have any worthwhile use. Typical blues get pretty much ignored, which makes no sense because blue has the higher energy potential.

Actually, no. If you look at the color of the solar panel, you'll find its wavelength gap that it doesn't pick up light from

Actually, no. if you would look at the reflectance of a solar panel with a spectrophotometer, you'll discover that, although (for example) silicon panels do look blue, even in the blue the reflectance is very low-- about 8% or so until you get below about 250 nm, where there's just not that many photons in sunlight. It just "looks" blue, because the reflectivity in the blue, low as it is, is more than the reflectivity elsewhere in the visible spectrum.

I suppose I should clarify that comment, since I'm sure it'll be read wrong-- I said "Silicon cells roll off for wavelengths below about 1000 nm"... what I'd intended to say here is that the performance drops to zero for wavelengths "longer" than about 1000 nm. ("below" meaning lower in energy, but longer in wavelength.)

"You can't see the "wavelength gap where it doesn't pick up light"-- that's in the infrared, below the ability of your eyes to see. If you could see in that wavelength, though, the semiconductor would be transparent."

In the field, I have equipment that I can wear and allow me to see a 'representation' of IR light across different wavelengths. It's quite accurate.

"Blue does have higher energy per photon, but the spectrum has far fewer photons there."

Exactly. Take a look at that curve: "blue" is the part to the left of the peak, where it drops off abruptly below about 475 nm, on the far left side of the curve. Power is the integral of the curve-- what fraction of the power in the spectrum is to the left of 475 nm?

There is more power in blue getting through out atmosphere than any other wavelength.

Integrate.

(It will also help if you plot the spectrum in terms of photons per square meter per unit energy [thulescientific.com], versus energy (in eV), since, like the eye, solar cells are quantum devices, and this is actually the response function. In fact, if

When I skimmed the summary I thought it was gray goo [wikimedia.org] time already. On closer reading, however, it appears that the molecules still need to be given a push to reassemble. The article doesn't answer the question of how much energy is needed to remove the surfactant.

And now they will have patented the hell out of the technology so no-one touches it without having to pay. Of course, this is the way universities make money. Ugh. I still hate the "patent courses" we got in our engineering education... And the teams of helpful university people in the patent office, just chomping at the bit to harvest yet another patent.... or maybe I am just being too negative.

And now they will have patented the hell out of the technology so no-one touches it without having to pay.

Only for 20 years, which IMO is reasonable, unlike copyrights which are NOT reasonable. Giving a truly limited time monopoly does further innovation, while the virtually unlimited copyright terms do not. I'm sure it cost a lot of money to develop this tech, without the limited monopoly it would be much harder to recoup the investment.

Sure, but it is universities in this case, which should not have to worry (much) about the money it cost. The problem I see is that I now encounter patents of fields I consider doing research in. In order not to enter legal territory, it is safer for me to research something else.

So if others do as I do, there will be a lot less research than what could have been done in 20 years if there were no patents. It isn't that patents are stopping innovation, they are just slowing it down to a glacial pace.

Every time I read a new material or new technology or gadget using nano-technology and nanotubes and such, I always wonder whether the inventors have thought of how they would dispose of the stuff so it doesn't harm the environment when it is EOL'ed. This, IMO, is a much neglected part of any news story which extols the virtues of nano-technology enabled foobar invention.

The nice things about plant cells or structure is that you can grow them. In this case I can only guess that it would probably even be more efficient than to "mine" forest. Also you wouldn't need so much of it because you don't use it for its energy content, but for its energy conversion capacity. That's huge difference.

And just think of all the Carbon Dioxide we can use up in the process. And before you start blathering about night time when they consume Oxygen... well duh, solar cells... just leave the bloody light on !

Per the article it's not nearly as biological as "plant-inspired" makes it sound.

They are using the photovoltaic effect to generate electricity on some set of proteins. Then carbon nanotubes conduct the electricity from the proteins to a common circuit. They are using phospholipids (whatever phospholipids are) along with the nanotubes to coerce proper alignment between the nanotubes and the proteins in the photovoltaic reaction sites.

The combination works pretty well (40% efficiency with sparsely populated functional structures in the solution for the prototype) until it starts to break down. The inspiration from plants is mainly that they can introduce a substance (a surfactant more specifically, although the blurb doesn't specify which) that breaks the stuff down fast, then filter the surfactant out through a membrane and the working portion self-assembles again at full efficiency.

It's this repeatable self-assembly that was biologically inspired, and it's probably necessary for high-efficiency photovoltaic solar cells since pretty much everything more efficient than silicon does break down over time. By not just accounting for the breakdown, but doing it early and often and performing a repair phase through self-assembly, it is hoped they can have high efficiency solar cells with long lifespans.

Phospholipids are little cute guys that make up your cellular membrane (a phospholipid bi-layer). They look something like this (in as much justice as ascii can do):

o=;

They have a phosphate head (that's the round bit) with two lipid tails, one saturated fat, and one unsaturated fat.

The phosphate side is hydrophilic (it likes water) and the lipid side is hydrophobic (doesn't like water). So a whole bunch of them will collect together tail-to-tail and side-to-side to make your semi-permeable cellular membra

I'm no expert on the matter, but I am hopeful for the tech like most geeks. From what I understand from reading articles about other work in the field and watching documentaries about it, 30% is common in the lab and even 50% or 60% is expected from some of the current work, but breakdown is rapid. The breakdown, in most cases, is caused by being exposed to sunlight and creating electricity from the exposure. Sometimes the efficiencies are down to 5% to 15% in a matter of hours or days.

Phospholipids are a class of lipids and are a major component of all cell membranes as they can form lipid bilayers. Most phospholipids contain a diglyceride, a phosphate group, and a simple organic molecule such as choline; one exception to this rule is sphingomyelin, which is derived from sphingosine instead of glycerol. The first phospholipid identified as such in biological tissues was lecithin, or phosphatidylcholine, in